Charles Darwin

Charles Darwin (12 February 1809-19 April 1882) was a British naturalist, geologist, and biologist who was known for his contributions to the science of evolution. He authored On the Origin of Species (1859), which created the idea of natural selection (the means by which species adapt to survive over the course of time), as well as The Descent of Man (1871), which proposed the idea that humans evolved from, and are related to, apes.

Biography
Charles Darwin was born in Shrewsbury, Shropshire, England in 1809, and he came from a prominent family of abolitionists. He spent the summer of 1825 as an apprentice doctor, and he went on to attend the University of Edinburgh Medical School, where he neglected his medical studies in favor of taking part in scientific debates. He later studied at Christ's College, Cambridge to become an Anglican parson, but he preferred riding and shooting to studying. In 1831, he came in tenth out of 178 candidates for the ordinary degree, and, after leaving school, a friend proposed him as a suitable naturalist for a place on the HMS Beagle, which would chart the coastline of South America. For five years, starting on 27 December 1831, the HMS Beagle travelled the world, and Darwin spent most of that time on land investigating geology and making natural history collections. He came to believe that there was no unbridgeable gap between humans and animals, and, while researching finches on the Galapagos Islands, he noticed that there were twelve different species. He discovered that their different beak shapes were related to what they ate, and he came up with the idea that these finches had adapted to their new environments through physical alterations; if they did not adapt, they could not find food and, therefore, not survive. By mid-March 1837, he speculated that one species could change into another to explain the geographical distribution of different species, and he became mired in work due to his theories. His travels aboard the Beagle established him as an eminent geologist, and he became a famous author after publishing his journal. As a budding biologist, he believed that animals passed down genetic information through "pangenes", although Gregor Mendel would later discover that this information - the gene - was instead contained in germ cells which created human reproductive materials through meiosis.

However, Darwin's theory that all species of life have descended over time from common ancestors was controversial. Devout Anglicans believed that the concept of evolution was incompatible with Christianity, which taught that God created all living beings, and that they could not evolve independently of him. His own wife, his cousin Emma Wedgewood, was also devoutly religious, and Darwin was hesitant to publish his findings until the 1850s, when fellow naturalist Alfred Russel Wallace made similar discoveries of natural selection in the East Indies. In 1859, Darwin published On the Origin of Species, publishing his theory of evolution with compelling evidence. In a joint publication with Wallace, he introduced his scientific theory that the struggle for existence has a similar effect to the artificial selection in selective breeding, a process which he called "natural selection", or, "the survival of the fittest".

Darwin went on to examine human evolution and sexual selection in The Descent of Man in 1871, in which he introduced the even more controversial theory that humans evolved from apes, and that all life forms evolved from a single common ancestor. These views were directly opposed to the conservative Victorian society's acceptance of the Bible as the only source of information on human creation, but, undaunted, he published The Expression of Emotions in Man and Animals in 1872 and The Formation of Vegetable Mould, through the Action of Worms in 1881. He died in Downe, Kent in 1882 at the age of 73, and he has been described as one of the most influential figures in human history, as his theory of evolution is now widely accepted and considered a foundational concept in science.